title: Antifungal Activity of the Noncytotoxic Human Peptide Hepcidin 20 against Fluconazole-Resistant Candida glabrata in Human Vaginal Fluid.
abstract: Vaginal infections caused byCandida glabrataare difficult to eradicate due to this species' scarce susceptibility to azoles. Previous studies have shown that the human cationic peptide hepcidin 20 (Hep-20) exerts fungicidal activity in sodium phosphate buffer against a panel ofC. glabrataclinical isolates with different levels of susceptibility to fluconazole. In addition, the activity of the peptide was potentiated under acidic conditions, suggesting an application in the topical treatment of vaginal infections. To investigate whether the peptide activity could be maintained in biological fluids, in this study the antifungal activity of Hep-20 was evaluated by a killing assay in (i) a vaginal fluid simulant (VFS) and in (ii) human vaginal fluid (HVF) collected from three healthy donors. The results obtained indicated that the activity of the peptide was maintained in VFS and HVF supplemented with EDTA. Interestingly, the fungicidal activity of Hep-20 was enhanced in HVF compared to that observed in VFS, with a minimal fungicidal concentration of 25 μM for all donors. No cytotoxic effect on human cells was exerted by Hep-20 at concentrations ranging from 6.25 to 100 μM, as shown by 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide tetrazolium salt (XTT) reduction assay and propidium iodide staining. A piece of indirect evidence of Hep-20 stability was also obtained from coincubation experiments of the peptide with HVF at 37°C for 90 min and for 24 h. Collectively, these results indicate that this peptide should be further studied as a novel therapeutic agent for the topical treatment of vaginalC. glabratainfections.
authors.affiliation: Dipartimento di Biologia, Università di Pisa, Pisa, Italy.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Del Gaudio
authors.affiliation: Dipartimento di Biologia, Università di Pisa, Pisa, Italy.
authors.forename: Lisa
authors.initials: L
authors.lastname: Lombardi
authors.affiliation: Dipartimento di Ricerca Traslazionale e delle Nuove Tecnologie in Medicina e Chirurgia, Università di Pisa, Pisa, Italy.
authors.forename: Giuseppantonio
authors.initials: G
authors.lastname: Maisetta
authors.affiliation: Dipartimento di Ricerca Traslazionale e delle Nuove Tecnologie in Medicina e Chirurgia, Università di Pisa, Pisa, Italy.
authors.forename: Semih
authors.initials: S
authors.lastname: Esin
authors.affiliation: Dipartimento di Ricerca Traslazionale e delle Nuove Tecnologie in Medicina e Chirurgia, Università di Pisa, Pisa, Italy.
authors.forename: Giovanna
authors.initials: G
authors.lastname: Batoni
authors.affiliation: Istituto di Microbiologia, Università Cattolica del Sacro Cuore, Roma, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Sanguinetti
authors.affiliation: Dipartimento di Biologia, Università di Pisa, Pisa, Italy.
authors.forename: Sonia
authors.initials: S
authors.lastname: Senesi
authors.affiliation: Dipartimento di Biologia, Università di Pisa, Pisa, Italy atavanti@biologia.unipi.it.
authors.forename: Arianna
authors.initials: A
authors.lastname: Tavanti